Phone calls involving voice data may traverse various networks including a local exchange carrier (LEC) network as well as mobile communication networks. As the voice data traverses the various networks, the data may be converted into various formats such as time-division multiplexing (TDM) trunking format or session initiation protocol (SIP) format. This is due in part to some mobile communication networks transitioning network equipment to support SIP formats, while LEC networks continue to maintain legacy infrastructure including switches and trunks that use TDM protocols. In some situations, a LEC network may charge other companies for use of the TDM resources, for instance for the service of terminating a voice call by way of a TDM trunk maintained by the LEC network.